power generation senario
TRANSCRIPT
Coal Power Generation in India and its Role in Economic
Efficiency
Symposium on Sustainable Power Supply Mix in the Future
Prosanto Pal
The Energy and Resources Institute, India
20 November 2015 Bangkok
Outline
Power sector in India Coal supply Generation technologies
Power sector in India – An overview
Power generation mix in India Thermal based power accounts for 70% of total generation Coal accounts for more than 80% of thermal mix
Per Capita Consumption- 870 kWh/Yr is very low Overall deficit 3.6%; Peak deficit 4.7%
Generation capacity
Installed capacity (2015) : 280,000 MW
Capacity doubled in 8 years • 140,000 MW (2007) • Average annual growth
rate : 8.5% Average capacity
addition was 22,000 MW per year in last 4 years
Sector-wise mix
Planned capacity additions till 2017 Thermal 50,000 MW; Hydro 7,200 MW; Nuclear 1,500 MW
NTPC Barh (2 X 660 MW) Bongaigaon Mauda
1320 MW 750 MW 660 MW
IL&FS Tamil Nadu, Cuddalore Phase 1 (2 X 600 MW) Phase 2 (3 X 800)
1200 MW 2400 MW
Maharashtra State Power Generating Co Kordi Chandrapur Parli
1980 MW 500 MW 250 MW
Prayagraj Power Generation Co, Bara, UP (3 X 660) 1980 MW
UP Rajya Vidyut Nigam Obra (2 X 660) Anpara Unit II
1320 MW 500 MW
KSK Mahanadi, Akalatara, Chhattisgarh Unit III & Unit IV(2 X 600)
1200 MW
Ultra mega power projects (UMPP) Completed projects Tata Power, Mundra, Gujarat (5 X 800 MW) : 4000 MW Reliance Power, Sasan, MP (6 X 660) MW) : 3960 MW Under construction/Awarded Reliance Power, Krishnapatnam, AP (5 X 800 MW) : 4000 MW Tilaiya (Jharkhand) Bidding process for 4 more units will be announced during the
financial year The Government of India is focusing on setting-up of 16 UMPPs with supercritical parameters
Installed generation capacities of 4000 MW per unit UMPPs are located either in pithead (domestic coal) and coastal
(imported coal)
Issues with other planned UMPPs Out of 16 proposed UMPPs, each of 4000 MW only 4 were
awarded since 2005-06
Most proposals stalled due to: Delays in land acquisition Policy changes envisaged
Coal linkage (assured fuel supply commitments from the government)
Swaping of coal among power plants to optimise transportation costs
New tariff policies formulated – proposes mandatory bidding process and differential tariffs
Bidding norms and coal linkages are being finalised
Coal supply
Domestic production of coal
Largest energy source; domestic production ~ 570 million tonnes • Proven reserves 126 billion tonnes • Open casting mining predominant • Indian coal has high ash content, variations in calorific
value and presence of extraneous matter Domestic production not keeping-up with
demand due to: Mining constraints (techno-economic viability) Infrastructure bottlenecks Environmental regulations
Coal Quality High ash content & low calorific value of coal Low sulphur content
Coal imports
Large quantities imported (~ 220 million tonnes) • Major imports from Indonesia, South Africa and
Australia • Only 10-15% imported coal can be in existing boilers
Projected to increase to 900 million tonnes in 2030
Coal washing
Washing requires especially before transporting long distances
• Current capacity 145 million tonnes
Need for capacity additions • No significant increase in recent years
Need for improvement in washing technologies • Problems of wet coal to power plants
Generation technologies
Supercritical Steam Cycle Technology
• More than 600 supercritical coal fired boilers in operation worldwide.
• Prevalent cycle parameters : • Pressure – 246 to 250 kg/cm2
• Temp - 538 oC to 600 oC
• Preferred steam parameters include high steam temp (566 to 593 oC) depending upon site specific techno economics.
• Increase in pressure and main & reheat temp more than 537 oC leads to significant improvements in heat rate
Advantages of supercritical steam cycle technology
• Supercritical units have higher plant efficiencies than subcritical units because of higher steam parameters
• Gross plant efficiency of supercritical units are around 40-41% compared to 38% of subcritical based units
• Gross plant efficiency of ultra-supercritical units are around 41-42% (280 ata/593 oC/593 oC)
• At international level, Advanced ultra-supercritical units have reached plant efficiencies of 47-49%
2-3%
Fuel saving
Reduced fuel costs due to improved plant efficiency
Other advantages
• Significant improvement of environment by reduction in CO2 emissions
• Plant costs less as compared to other clean coal technologies
• Much reduced NOx, SOx and particulate emissions
Evolution of coal based plants in India
Period 1960s 1970s 1977 1983 Under
Constrn.
Unit Size (MW) 60-100 110-120 200-250 500 660-800
Turb Inlet Pressure
/ Temp
70-90 ata
490-5350C
130 ata
5350C
130 ata
5370C
170ata
5370C
247 ata
5370C
Reheat Temp. No reheat 5350C 5370C 5370C 5650C
Turbine Cycle Heat
rate (kCal/kWh)
2370 2060 to
2190
1965 1945 1900
Gross efficiency (%) 30.5 33 to 35 37.2 37.6 38.5
Future outlook Coal will continue to have maximum share towards
installed capacity for power generation in India
Clean Coal Technologies such as supercritical, ultra
supercritical and advanced ultra supercritical system
will be the focus in future power projects
800-1000 MW unit plants more suitable to handle
Indian coal but technology cooperation with
international manufacturers
